The tissue will be washed again with Phosphate Buffered Saline (PBS) that included antibiotic and antimytotic, cut into small pieces under aseptic conditions, treated with 0.06% collagenase type II (In vitrogen) and dispase, shaken with an incubator (CO2 incubator, Forma Scientific) containing 5% CO2 at 37°C for 4 hours, and centrifuged at 1,000 (Revolution Per Minute) for 10 minutes (large-capacity tabletop centrifuge).